Process for chemically extracting pure metals from their ores at a temperature lower than the fusing-point of the metals to be extracted.



ED.- s'rnrns PA orrron.

FABLEY GRANGER CLARK AND ALEXANDER THOMAS STUART, OF TORONTO, ONTARIO,

' CANADA, .ASSIG-NORS TO THE TORONTO POWER COMPANY LIMITED, OF TORONTO,

ONTARIO, A CORPORATION 015 ON TABIO.

PROCESS FOR GHEMIOALLY EXTRACT ING- -TE1EPERATUBE LOWER THAN THE FUSING-POINT OF mmcrnn.

PURE METALS FBOM'THEIR'ORES AT A THE METALS TO BE aacaosa. R Drawing.

To all whom it may concern:

Be it known that we, FARLEY GRANGER CLARK, a citizen of the United States of America, and ALEXANDER THOMAS STUART, a subject of the King of Great Britain, both residing at the city of Toronto, in the county of York and Provinceof Ontario, Dominion of Canada, have invented certain new and useful improvements in processes for chemically extracting pure metals from their ores at a temperature 'lower than the fusingpoint of the metals to be extracted; and we hereby declare that the following is a full, clear, and exact description of the same.

This invention relates to a process for chemlca'lly extracting, at a temperature lower than the fusing point of the metal to be extracted, pure metals from their ores by decomposition in the presence of a gaseous reagent which will combine with certain constituent matter to-be removed, in cluding oxygen, sulfur, phosphorus, and manganese, the products of the combination being gaseous and passing awayfrom the reaction zone under the conditions of the process, and the isolated metal and the aangue matter which'may not be attacked by e gaseous reagent retaining their original solid phase, to be separated by subsequent treatment. r r

While dry hydrogen is preferable as the" reagent, asthis gas does not add impurities to the ore or metal undertreatment, and readily combines with certain substances, to .be removed to form gases which, as 'a result of the recombination, pass away from .the reaction zone, together with the excess free hydrogen, theamount-of which is determined by the conditions of the process, any other reagent having like properties, such as carbon 'monom'd, may be substituted for the hydrogen. As such gases contain no extraneous substances except those which can be readily removed, the excess free hyeqdrogen contained in such gases is recoverable and; reusable. This is'of the utmost importance for economic reasons, as by the recovery and reuse of this excess free hydrogen, an amount of hydrogen approximating the theoretical minimum required elemental constituents of which may "enter OXCBS p fi on rr-mm mm Patented June 11, 1918.. Application filed July 5, 1917. Serial No. 178,635.

Satisfactory results have been attained by" passing-a controllable current .of dry hyogenthrough'a reaction zone countercurrent to the flow of ore,'the rate of thereaction-being limited only by the capacity to deliver the required heat to the flow of ore and. hydrogen, and being practically in stantaneous when the amounts of ore and hy-' drogen and heat input are correctly regu lated.

- The best results are obtained by the direct application of electrical heat the reaction zone,'or to the ore and hydrogen immediately before entering the same, or the similar indirect application of heat from fuel firing, either gaseous, liquid or SOlld,

the degree of heat being preferably suflicient only for the decomposition of the compounds of the substances and their recombination with the hydrogen. 7 This is of the utmost advantage-over processes carried on at temperatures at-or above the fusion points of the contained metal or '75 other ore constituent, as the ore, and often the reducing agent, contain impurities, such as ash, sulfur, carbon,- phosphorus, manganese, magnesia, lime, alumina, silica, etc., the 0 8 into and alloy themselves with the metal and form' an inferior product which must be Submitted to a refining process for the production of high-grade metals.

Iron contained in iron ore, either 1n lump or pulverized form may beisolated in a pure metallic state by passingthe ore and hydrogen through a reactlon zone at a temperature which maybe as low as 400 degrees centigrade, the hydrogen being so caused to circulate, preferably countercurrent to the ore, that certain substances to beremoved, such as oxygen, sulfur, phosphorus and manganese, combine with the hydrogen instantly when decomposition occurs, forming with the hydrogen, gaseous compounds which pass away from the reaction zone and leave the pure metal and the gangue matterin their original solid phases chemically iiii nn ds, to a 'th e' y ogen compoun go or withe excess free hydrogen, after passing from the reaction zone are collected, such free hydrogen being readily separated from the hydrogen compounds .by usual methods, and after such separation, returned to the reaction zone for further use, the amount of the excess free hydrogen being fixed by the equilibrium constant for the particular conditions of the reaction in volved, and as-this amount is necessarily considerable, its collection, separation and reuse is of the utmost-importance for the economical Working of the process.

Thehydrogen compounds, being also of 4 economic value, are recovered for use, as

many of these compounds, such as phosphorus in its various forms, have relatively high market values, and often are worth more than the metal itself.

This process not only permitsof the isolation of the metal from its ore, but it also permits of the economical extraction of pure metal from ores, regardless of their physi- Having thus fully described the nature of our invention, what we claim as new and desire to secure by Letters Patent, is

1. A process for extracting pure metal,

from its ores and removing undesirable constituents therefrom, which consists of passing ore and a gaseous reagent in regulable quantities through a reaction zone at a temperature sufficient to cause the reactlon, but

. below the fusing pointof the metal, to efiect 'zone at a temperature suflicient to'cause the reaction, but below the fusing point of the metal, to efi'ect the isolation of the. contained metal in a pure state, the gaseous reagent combining with the oxygen, sulfur, phosphorus, and manganese as compounds thereof. 3. A process for extracting pure metal from its ores and removing oxygen, sulfur, phosphorus, and manganese therefrom, which consists of passing ore and a gaseous reagent in regulable quantities through a reaction zone at a temperature sufiicient to cause the reaction, but below the fusing point of the metal, to effect the isolation of the contained metal in a pure state, the gaseous reagent combining with the oxygen, sulfur, phosphorus, and manganese as compounds thereof, and then recovering such compounds.

loronto, June 14th, 1917.

rrrtrr smear GLARK. ALEXANDER THOMAS STUART.

Signed in the presence of i a"; 2 s H. RIGtsli 9 WM. Vornrrxnn 

